Create a dummy irq driver

drivers/misc/Makefile

@@ -9,7 +9,7 @@ obj-$(CONFIG_AD525X_DPOT)	+= ad525x_dpot.o
 obj-$(CONFIG_AD525X_DPOT_I2C)	+= ad525x_dpot-i2c.o
 obj-$(CONFIG_AD525X_DPOT_SPI)	+= ad525x_dpot-spi.o
 obj-$(CONFIG_ATMEL_SSC)		+= atmel-ssc.o
-obj-$(CONFIG_DUMMY_IRQ)		+= dummy-irq.o
+obj-$(CONFIG_DUMMY_IRQ)		+= dummy-irq.o dt-dummy-irq.o
 obj-$(CONFIG_ICS932S401)	+= ics932s401.o
 obj-$(CONFIG_LKDTM)		+= lkdtm/
 obj-$(CONFIG_TIFM_CORE)       	+= tifm_core.o

drivers/misc/dt-dummy-irq.c

@@ -0,0 +1,82 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * DT Dummy IRQ handler driver.
+ *
+ * Copyright (C) 2013 Jiri Kosina
+ * Copyright (C) 2019 Daniel Palmer
+ */
+
+#include <linux/module.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/of_irq.h>
+
+#define DRIVER_NAME "dummy-irq"
+
+static irqreturn_t dummy_interrupt(int irq, void *data)
+{
+	static int count = 0;
+
+	if (count == 0) {
+		printk(KERN_INFO "dummy-irq: interrupt occurred on IRQ %d\n",
+				irq);
+		count++;
+	}
+
+	return IRQ_NONE;
+}
+
+static int dummy_probe(struct platform_device *pdev)
+{
+	int count, i, irq, ret;
+
+	count = of_irq_count(pdev->dev.of_node);
+
+	dev_info(&pdev->dev, "dummy-irq: registering %d irqs\n", count);
+	for(i = 0; i < count; i++){
+		irq = irq_of_parse_and_map(pdev->dev.of_node, i);
+		if (!irq){
+			dev_err(&pdev->dev, "failed to register irq at %d -> %d", i, irq);
+			continue;
+		}
+
+		ret = devm_request_irq(&pdev->dev, irq, dummy_interrupt, IRQF_SHARED,
+				dev_name(&pdev->dev), &pdev->dev);
+		if(ret){
+			dev_err(&pdev->dev, "failed to request irq at %d -> %d", i, ret);
+			continue;
+		}
+
+
+		dev_info(&pdev->dev, "dummy-irq: registered irq at %d -> %d", i, irq);
+	}
+
+	return 0;
+}
+
+static int dummy_remove(struct platform_device *pdev)
+{
+	return 0;
+}
+
+static const struct of_device_id dummy_dt_ids[] = {
+	{ .compatible = "dummy-irq" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, msc313_fcie_dt_ids);
+
+static struct platform_driver dt_dummy_driver = {
+	.probe = dummy_probe,
+	.remove = dummy_remove,
+	.driver = {
+		   .name = DRIVER_NAME,
+		   .of_match_table = dummy_dt_ids,
+	},
+};
+
+module_platform_driver(dt_dummy_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Daniel Palmer <daniel@0x0f.com>");
+MODULE_DESCRIPTION("Dummy IRQ handler driver");